Spectrum Sharing Through Receiver Beacons in Fading Channels

Ideal spectrum sharing should try to make the pair of co-channel secondary transmitter (ST) and primary receiver (PR) into a critical state that the ST is the PR’s protection boundary while the PR is the ST’s interference boundary. Based on the conditions of beacon sensing and secondary transmitting power in that state, we analyze the critical interference probability (CIP) caused by the fading and nonreciprocity of the bidirectional channels, and give out the secondary transmit-power constraint (STPC) mechanism for given interference constraints the first time for spectrum sharing through receiver beacons in fading channels. It can be noted that, for high spectrum utilization the frequency of beacon channel should be chosen carefully so that its propagation characteristics can be highly correlated with its indicating primary band. The study is further extended to the scenario with multiple PRs tuned on the same primary band simultaneously as in broadcast services, where through statistical modeling of aggregate received beacon power, the CIP and STPC are given out with the nearest PR to the ST as the interference protection target.